Support additional pseudo-elements with arguments?

[philschatz]

There are drafts for CSS extensions that use arguments to pseudo-element selectors (ie ::slotted(.foo) or ::before(2)) to allow additional information.

Rather than something like hardcoding lib/parser/type/PseudoElement.js#L20 what if:

1. the parser allowed any pseudo-element to have optional arguments (instead of special-casing ::slotted(.foo)? or
2. the css-tree constructor took an additional configuration option containing all the valid pseudoelements and whether arguments were forbidden, allowed, or required?

Thanks again for all the parsing work!

[lahmatiy]

Yep, I thought about it, but had no any use case. I don't see any reason for any pseudo-element to be a functional-pseudo. Even it's not a standard yet ;)
I working on pseudos right now. So I'm going to do first point ;)

the css-tree constructor took an additional configuration option containing all the valid pseudoelements and whether arguments were forbidden, allowed, or required?

Yes, I believe it will be available later by setting custom consumer for pseudos, functions and at-rules. It's not ready yet, but it's likely to appear in future releases.

[lahmatiy]

Available in 1.0.0-alpha4